Cortex-A520 + A720 systems fail test PE 1

[hrw]

Mixing Cortex-A520 with A720 is one of things which Arm SoC vendors go for to have both performance and effective cores.

And then BSA ACS PE test 1 fails because they are not the same.

Primary PE Index: 0, ID_AA64DFR0_EL1  : 0x100F11F310305719 
        PE Index: 1, ID_AA64DFR0_EL1  : 0x100F11F010305719    FAIL
          Masked Primary PE Value : 0x100F11F310000000 
          Masked Current PE Value : 0x100F11F010000000 

Difference is on PSMVer. A520 does not have Statistical Profiling Extension at all while A720 can either not implement it or implement SPEv1p2 which value 0b0011 shows here.

  Primary PE Index: 0, ID_AA64MMFR1_EL1 : 0x1001111010312122 
          PE Index: 1, ID_AA64MMFR1_EL1 : 0x1001111011312122    FAIL
          Masked Primary PE Value : 0x1001111010010000 
          Masked Current PE Value : 0x1001111011010000 

The difference is SpecSEI field which has different value between A520 (0b0001) and A720 (0b0000).

Then there are differences on Performance Monitors registers too due to PMU event counters difference: 6 on A520, 20 on A720.

Should those be ignored by hardware vendor or by BSA ACS?